On Notice: Third State Responsibility and U.S. Airstrikes in the Caribbean and Pacific

[Mina Nur Basmaci is a Legal and Advocacy Fellow at the Center for Civilians in Conflict (CIVIC). She is a graduate of Washington University in St. Louis School of Law and a member of the American Branch of the International Law Association’s Study Group on Crimes Against Humanity.

John Ramming Chappell is an Advocacy & Legal Advisor at Center for Civilian in Conflict (CIVIC). In his work, he engages in advocacy and analysis related to U.S. lethal strikes.]

Since September 2025, the Trump administration has carried out a campaign of executions by airstrike in the Caribbean Sea and the Pacific Ocean that it characterizes as operations against “narco-terrorists.” The administration has not provided credible information to support its claims, and in actuality, has killed at least 157 civilians thus far. Because these killings occur outside any recognized armed conflict, without due process, and target individuals allegedly transporting drugs—conduct that neither constitutes an imminent threat nor a direct participation in hostilities—the U.S. has committed extrajudicial killings, and possibly crimes against humanity, under international law.

President Trump has nevertheless indicated that the strikes will continue, including through a recently announced joint operation with the Ecuadorean government. As operations persist and expand, the legality of the campaign is an urgent and ongoing question—not least for third States, like Ecuador, that are supporting U.S. operations.

Indeed, the U.S. government is not carrying out these strikes—and therefore committing human rights violations—alone. The U.S. relies on security cooperation and access to military bases to identify and target vessels in the Caribbean and Pacific. Third States that have provided intelligence or other forms of support to U.S. lethal strikes may incur legal responsibility for their participation in these unlawful acts. They thus represent key pressure points for preventing and deterring the extrajudicial killings and holding those responsible to account.

To that end, several major U.S. security partners in the Caribbean and Pacific, including the United Kingdom—a member of the Five-Eyes intelligence sharing alliance—the Netherlands, Colombia, and Canada, have ceased intelligence-sharing in connection with the lethal strikes. Doing so is a concrete means of condemning the strikes and avoiding complicity in human rights violations.

This article outlines the legal framework governing third State responsibility and identifies States that may be contributing to the strikes, based on both their security cooperation arrangements with the United States and their political positioning regarding the strikes. It seeks to place States on notice of their incurred legal risk and to serve as a reference for legal practitioners and civil society in identifying priority targets for advocacy.

Legal Framework Governing Third State Responsibility

Extrajudicial killings and crimes against humanity are prohibited under customary international law such that States can be held liable for their commission. Importantly, third States can incur legal responsibility for aiding or assisting another State in their commission of internationally wrongful acts. This principle appears in various sources of international law, including treaties—see Article 16 of the Articles on Responsibility of States for Internationally Wrongful Acts (ARSIWA)—and domestic and international jurisprudence.

Third States are responsible if they are (1) “aware of the circumstances making the conduct of the assisted State internationally wrongful,” (2) if their aid or assistance are “given with a view to facilitating the commission of that act, and must actually do so,” and (3) if the completed act would have been wrongful had it been committed by the third State itself.  The commentaries and reports accompanying ARSIWA, as well as scholarship and State practice, are inconclusive about whether mens rea under Article 16 requires both intent and knowledge, or whether knowledge is sufficient and can imply intent. The actus reus is more clear. A State’s aid or assistance need not be essential to the commission of the internationally wrongful act—significantly contributing is enough.

Recognized examples of aiding and assisting another State’s internationally wrongful acts, and thereby incurring legal liability for such acts, include:

“knowingly providing an essential facility or financing the activity in question” and providing “material aid to a State that uses the aid to commit human rights violations.”

The United States has long depended on security cooperation to operationalize its counternarcotics efforts in the Caribbean and Pacific, including through bilateral and multilateral agreements with States in the region as well as major powers. Intelligence sharing, granting access to bases, and hosting radar, surveillance, and other military or dual-use equipment by third States readily satisfy the actus reus of aiding and assisting, as they significantly contribute to the identification, tracking, and targeting process of suspected drug vessels.

The mens rea requirement is likewise difficult for cooperating third States to contest. The U.S. has conducted the strikes openly and has publicly articulated its policy of authorizing lethal military force against suspected drug vessels, which ordinarily should be subject to interdiction as part of a law enforcement, not military, paradigm. The U.S.’ legal justification has accordingly been almost universally rejected by legal experts. Speaking at a conference on cartels and the Americas, White House Deputy Chief of Staff Stephen Miller told Latin American military leaders that cartels:

“can only be defeated with military power…You’re dealing with a lot of lawyers in your own country, I’m sure. You have my permission not to listen to them.”

In these circumstances, States providing operational support cannot plausibly claim ignorance on what conduct their assistance facilitates. This inference is further reinforced by U.S. sustained diplomatic engagement, including frequent visits by officials to regional States to seek support for the strikes, discussed below, and statements encouraging these States to use military force against cartels. At minimum, these surrounding circumstances establish constructive knowledge.

Legal Framework Governing Individual Criminal Responsibility in Third States

U.S. maritime strikes in the Caribbean and Pacific also implicate individual criminal responsibility under international criminal law. Specifically, State officials and other individuals cooperating with the U.S. during its unlawful campaign can be held liable for aiding and abetting U.S. extrajudicial killings and crimes against humanity.

Aiding and abetting as a mode of liability is articulated in, inter alia, Article 25(3)(c) of the Rome Statute and in the statutes of ad-hoc tribunals and domestic systems. To be held liable, the given aid must have a substantial effect on the commission of the crime. The individual must also generally have knowledge that their conduct aids or facilitates the commission of an international crime. Depending on the jurisdiction, their knowledge may be actual or constructive and may be inferred from the surrounding circumstances. For specific intent crimes, a higher level of mens rea may be required; the International Criminal Court accordingly imposes a purpose standard.

Crucially, following orders does not immunize perpetrators from responsibility. Military personnel and other State agents have a legal duty to refuse manifestly unlawful orders or orders that they know are unlawful—see, for example, Rule 916(d) of the United States’ Manual for Courts-Martial—and failure to do so may result in criminal prosecution.

Which States Are Contributing to U.S. Strikes in the Caribbean and Pacific?

Though the full roster of U.S. security partners is not publicly disclosed, discernible patterns exist. This article holistically assesses a constellation of legal, political, and operational factors to identify States that are cooperating with, likely cooperating with, or may be positioned to cooperate with the U.S. strikes policy. This article does not intend to definitively assess whether specific States meet the legal threshold for responsibility under a theory of aiding and assisting.

States Cooperating with U.S. Strikes

The Dominican Republic has confirmed its cooperation with U.S. boat strikes. The government helped locate a speedboat during one of the strikes and allegedly seized cocaine afterwards. As well, Secretary of Defense Pete Hegseth traveled to the Dominican Republic the week of November 26, 2025 and obtained additional access to its airbase.

States Likely Cooperating with U.S. Airstrikes

The following States support the maritime strikes policy and have recently agreed to provide basing, intelligence, and other forms of assistance that may be used to materially support the strikes.

Trinidad & Tobago has praised the U.S. strikes and its Prime Minister, Kamla Persad-Bissessar, met with Gen. Dan Caine, U.S. chairman of the Joint Chiefs of Staff, on November 25, 2025. They exchanged views on “challenges affecting the Caribbean region, including the destabilizing effects of illicit narcotics…and transnational criminal organization activities.” After their meeting, Trinidad & Tobago confirmed that the U.S. had installed a new radar system in the country. The Prime Minister narrowly denied its relation to U.S. operations in Venezuelan territory but admitted it was to be used at least for narcotics trafficking. The State has also recently approved U.S. military aircraft transit in its airports, demonstrating a ramp up of support.

Trinidad & Tobago, Panama, and El Salvador have also hosted U.S. forces since the strikes began. Panama and Trinidad & Tobago hosted U.S. military exercises and joint training. El Salvador, meanwhile, hosted additional deployments of U.S. military aircraft.

In Ecuador, while President Noboa has expressed support for U.S. strikes, a referendum to re-establish foreign military bases, including a U.S. base to assist in part with “narco-terrorism,” recently failed to pass. The Ecuadorean administration has nonetheless found other avenues to support U.S. military force against cartels in the region, including a recently announced joint operation in their territory that has resulted in a land strike thus far. It is unclear whether their operations will include maritime strikes, but it is important to note the country’s Pacific border and explicit support otherwise.

Lastly, the U.S. recently requested the installation of temporary radar equipment in Grenada, which is located directly north of Venezuela and may contribute to U.S. airstrikes in the Caribbean. The Grenadian government has criticized the maritime strikes but is reportedly still reviewing the request and has deferred a decision for now.

Broader Counternarcotics Cooperation

Several States with a regional presence—the Dominican Republic, Suriname, Paraguay (signed most recently, on December 15, 2025), Ecuador, Panama, Trinidad & Tobago, Bahamas, Guatemala, and Antilles (the Netherlands) — have counternarcotics-related security agreements with the United States. These agreements, combined with the States’ proximate location relative to the strikes and other indicators described in this article, may indicate increased likelihood of cooperation in the maritime strikes campaign.

Admiral Alvin Holsey, the former head of U.S. Southern Command, visited Guyana in late November 2025 to promote regional security. He met with senior Guyanese commanders to discuss their long-standing regional defense alliance, including with respect to counternarcotics.

The newly announced “Shield of the Americas,” or the Americas Counter Cartel Coalition, brings together 17 States—the United States, Argentina, El Salvador, Bolivia, Costa Rica, Chile, the Dominican Republic, Ecuador, Guyana, Honduras, Panama, Paraguay, Trinidad and Tobago, the Bahamas, Belize, Guatemala, and Peru—is a U.S.-led effort to coordinate military pressure against cartels in the region. Speaking at a summit in Miami, Donald Trump signaled increasing aggression ahead, saying the U.S. military was already “knocking the hell out of them, where we can” and warning “we’re going to go heavier,” while urging regional partners: “We need your help, you have to — just tell us where they are.” The coalition is framed as a commitment to “operationalize hard power,” and combined with other statements and security steps described in the article, could indicate implicit regional backing by these States and their potential direct cooperation with future U.S. boat strikes.

Notably, Guatemala, Belize, Honduras, Bolivia, and Chile have joined the Americas Counter Cartel Coalition but have also issued express statements condemning U.S. boat strikes. Their dual posture may reflect either hedging behavior or a change in posture which should be monitored.

Political Support for U.S. Strikes

Political vocal support for the maritime strikes can indicate a willingness to assist in their execution—especially when combined with the other indicators discussed in this article—as such rhetoric helps generate narrative legitimacy for the campaign.

Trinidad & Tobago, Guyana, Ecuador, the Dominican Republic, and the Cayman Islands (UK) have publicly and explicitly expressed support for the strikes.

As well, several States did not endorse the Community of Latin American and Caribbean States (CELAC) statement condemning U.S. military presence in the region, which may indicate tacit support. These States include: Argentina, Costa Rica, Ecuador, El Salvador, Guyana, Jamaica, Paraguay, Peru, and Trinidad & Tobago.

Several States have adopted the U.S.’ controversial framing of “narco-terrorism,” including through designating Cartel de los Soles as a “terrorist organization.” U.S. Secretary of State Marco Rubio designated Cartel de los Soles a Foreign Terrorist Organization on November 16, 2025, and the Trump administration has repeatedly described people killed by U.S. airstrikes in Latin America as “narco-terrorists” operating under or in connection with Cartel de los Soles. Cartel de los Soles is a term used to describe the Venezuelan government’s role in criminal activity and has been characterized by experts as not a real cartel. Nevertheless, the Dominican Republic, Ecuador, Argentina, and Paraguay have also designated Cartel de los Soles as a “terrorist organization.” These parallel designations suggest a degree of deference to the U.S. policy vision of a more militarized response to drug trafficking in the region. They also create a policy nexus that could facilitate regional cooperation, including support for U.S. maritime strikes in the Caribbean and Pacific as a means of targeting networks linked to Cartel de los Soles.

Synthesizing Findings

States such as the Dominican Republic, Trinidad & Tobago, and Ecuador exhibit the strongest convergence of cooperation indicators. A broader set of States, including Guyana, Paraguay, Panama, and El Salvador show partial alignment through at least two to three indicators. Taken together, these findings help identify which States may warrant closer scrutiny when assessing potential accountability for aiding or assisting U.S. maritime strikes and rallying calls for oversight and transparency.

Conclusion

U.S. airstrikes of boats in the Caribbean and Pacific have caused significant civilian loss, devastated the families and communities of the deceased, and contributed to regional instability—including the U.S. invasion of Venezuela and its capture of Nicolás Maduro, a sitting Head-of-State. The strikes mark a further erosion of human rights and respect for the rule of law at a pivotal moment for international law’s legitimacy. However—and as the International Court of Justice has emphasized in another case concerning U.S. transgressions in Latin America—non-practice does not negate the existence of a legal obligation but rather constitutes a breach of it, one that demands accountability. With the United States unlikely to shift course on its own, identifying third States that may be aiding or assisting the unlawful maritime strikes and reaffirming their obligations is central to the accountability process. This article has thus demonstrated that the Dominican Republic, Trinidad & Tobago, Ecuador, and other States who have cooperated or are likely cooperating with U.S. strikes must cease their support or risk incurring legal liability.